赤潮异弯藻和海洋原甲藻LSU rDNA扩增及序列分析

Amplification and Analysis of Partial Ribosomal RNA Large Subnunit Genes Sequences of Heterosigma akashiwo Hada and Prorocentrum micans Ehrenberg

利用引物 D1R和 D2 C扩增并测定了赤潮异弯藻 (H eterosigma akashiwo Hada)和海洋原甲藻 (Prorocentrum micans Ehrenberg)的 L SU r DNA D1与 D2序列 ,并与 Gen Bank中相关序列进行比较分析。结果表明 :在种内水平 ,所测的 H .akashiwo 6个株系之间共有 5个变异位点 ,序列H.k与 H.k- 2 ,H.k- 4均存在碱基替换 ;原甲藻属不同种内各株系之间的遗传距离为 0 .0 0 2～0 .0 2 3之间 ,所测序列 P.mi与 P.micans其他株系之间均存在碱基替换。在种间水平上 ,原甲藻属不同种之间的遗传距离在 0 .0 4 5～ 0 .139之间 ,大于种内遗传距离 ,每个种都具有特定的保守序列。根据序列间的遗传变异 ,可设计特异性的探针对不同株系和物种进行检测和计数。

The LSU rDNA partial sequences of marine algae, Heterosigma akashiwo Hada and Prorocentrum micans Ehrenberg were amplified with primers D1R/D2C and aligned with those in GenBank to assess the inter-and intraspecific variations. The intraspecific distances, calculated by the Kimura-2 parameters method, ranged form 0.002 to 0.023. Though the sequences were conservative within the same species, there were still some variation sites among different strains that could be used to design strains-specific probes. The genetic distances among species, within genus Prorocentrum, ranged from 0.045 to 0.139. Each species owns its conserved domains, by which species-specific probes can be designed to identify different Prorocentrum species.